On Dec 8, 2025, at 4:07 AM, Olivier Delcourt via ceph-users <ceph-users@ceph.io> wrote:

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Le 8 déc. 2025 à 09:36, Robert Sander via ceph-users <ceph-users@ceph.io> a écrit :

Hi,

Am 08.12.25 um 9:32 AM schrieb Nico Schottelius via ceph-users:

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since migrating to Squid (19.2.3), I get the following health warning: [WRN] BLUESTORE_FREE_FRAGMENTATION: 1 OSD(s) osd.25 0.806301

How large is this OSD?

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However while this is a warning, there seems to be no documented way of fixing it. What do I do with this warning / how to defrag the bluestore filesystem?

Even the IBM documentation recommends to contact the IBM support in this case: https://www.ibm.com/docs/en/storage-ceph/8.1.0?topic=bluestore-fragmentation...

My best bet is to just recreate the OSD.

Before that, what about trying to empty the OSD ( ceph osd reweight XXX 0) and when empty, put it back to business ( ceph osd reweight XXX 1) ?

I suspect that would do the trick, but would suggest instead "crush reweigh" so that the balancer doesn't get confused.